Fairway wood with titanium face member

ABSTRACT

A fairway wood head comprises a stainless steel body and a cup-shaped titanium alloy face member attached by silver-nickel brazing to the body. The face member is preferably of variable thickness, being thicker at it&#39;s center than at it&#39;s outer periphery. Weights are attached at the toe and heel, respectively, of the body, to resist twisting of the head during an off-center hit. Weights are attached in the sole of the body on opposite sides of a front-to-rear center line of the head to lower the center of gravity of the head. The head has a hosel which includes a stainless steel inner portion and a titanium alloy outer sleeve portion disposed around and attached to the inner portion.

The present invention claims priority under 35 U.S.C. §119 and/or §365 to U.S. Provisional Application Serial No. 60,633,322 filed on Dec. 6, 2004.

BACKGROUND

The present invention relates to golf clubs and, in particular, to fairway woods. The invention especially relates to fairway woods having a head comprised of a stainless steel body and a titanium front face.

Fairway woods are known whose head includes a titanium alloy faceplate attached to a stainless steel body. The use of titanium alloy for the faceplate reduces the weight of the club head, enabling faster head speed to be attained, as well as enabling the front face to perform a spring action for increased distance.

As shown in FIG. 9, it is also known to employ a titanium alloy faceplate 30 of variable thickness whose center region is thicker than the outer peripheral portion thereof. That enables the club face to perform an enhanced spring action which further increases the distance of a fairway shot. It is known to attach such a variable thickness faceplate to the body by a tungsten inert gas (TIG) welding along the thin outer peripheral portion of the faceplate at a location spaced from the upper and lower edges 31, 32 of the club face. The welding action causes the welded part of the thin peripheral portion to loose its beneficial flexibility. Since the height of the faceplate is relatively short, even a partial loss of flexibility has a significant adverse effect on the overall springiness of the faceplate.

It is also known that optimum directional accuracy of a wood shot can be attained when impact occurs at the center sweet spot of the club face, but that an off-center hit which is offset toward the toe or heel of the club, can cause the club to twist, thereby causing the shot to hook or slice.

Therefore, it would be desirable to minimize or obviate the above-described disadvantages and provide a fairway wood that is capable of producing longer and more accurate golf shots, even in the case of an off-center hit.

It would also be desirable to provide a fairway wood that is more forgiving of off-center hits.

It would be further desirable to provide a fairway wood that reduces backspin and increases the elevation of a struck ball.

It would moreover be desirable to provide a fairway wood that can more easily become airborne at the start of the backswing.

SUMMARY OF THE INVENTION

One aspect of the present invention relates to a fairway wood which comprises a body and a face member attached to a front side of the body. The face member includes a front portion and a rim projecting rearwardly from an outer periphery of the front portion. The front portion defines a front face of the wood. A rear portion of the rim is bonded to a seat of the body. The body comprises stainless steel and the face member comprises titanium, wherein a rear end edge of the rim is bonded to the seat of the body by silver-nickel brazing.

Preferably, the front portion of the face member is thicker than an outer peripheral portion thereof.

Preferably, first and second weights are mounted in a sole of the body on opposite sides of a horizontal front-to-rear centerline of the body.

Preferably, third and fourth weights are mounted in a toe portion and a heel portion, respectively, of the body.

Preferably, the body comprises stainless steel, and a hosel is provided which comprises a stainless steel cylindrical inner portion defined by part of the body, and a cylindrical outer sleeve portion telescoped onto and bonded to the inner portion. The outer sleeve portion is formed of a titanium alloy.

Another aspect of the invention relates to a fairway wood which comprises a body, a face member attached to a front side of the body, and four weights mounted in the body. First and second ones of the weights are mounted in a sole of the body on opposite sides of a horizontal front-to-rear centerline of the body. Third and fourth ones of the weights are mounted in toe and heel portions, respectively, of the body.

Another aspect of the invention relates to a fairway wood which comprises a body and a face member attached to a front side of the body. The body includes a sole. A front portion of the sole is flat and horizontal, and a rear portion of the sole is inclined upwardly and rearwardly from a location substantially midway between front and rear ends of the body.

A further aspect of the invention relates to a fairway wood which comprises a stainless steel body, a titanium alloy face member attached to a front side thereof, and a hosel comprising a stainless steel inner portion formed by part of the body, and a titanium alloy outer sleeve portion disposed around and attached to the inner portion.

BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the invention will become apparent from the following detailed description of preferred embodiments thereof in connection with the accompanying drawings in which like numerals designate like elements and in which:

FIG. 1 is a front perspective exploded view of a fairway wood according to the present invention.

FIG. 2 is a bottom perspective view of the fairway wood.

FIG. 3 is a bottom perspective exploded view of the fairway wood.

FIG. 4 is a bottom perspective view of the fairway wood.

FIG. 5 is a side elevational view of the fairway wood, with an added weight shown in exploded view.

FIG. 6 is a bottom plan view of the fairway wood with added weights shown in exploded view.

FIG. 6A is an enlarged fragmentary view depicting an alternative way of mating the rim of the face member with the seat of the body.

FIG. 7 is a schematic side elevational view of the fairway wood showing an enlarged effective hitting area and deepened center of gravity.

FIG. 8 is a schematic sectional view of the fairway wood showing a cross section of the variable thickness cup-shaped faceplate having an enlarged sweet hitting area.

FIG. 9 is a schematic side elevational view of a prior art fairway wood having a short sweet hitting area.

FIG. 10 is a cross-sectional view of a preferred face member according to the invention.

FIG. 11 is a schematic side elevational view of a fairway wood according to the invention illustrating the shape of the sole area.

FIG. 12 is a view similar to FIG. 11 of a prior art fairway wood.

DESCRIPTION OF PREFERRED EMBODIMENTS

Depicted in FIGS. 1-6 is a head 10 of a fairway wood comprising a stainless steel body 12, and a titanium alloy face member 14 attached to a front side thereof. The face member 14 is cup-shaped in that it comprises a front portion 16 and a rim or lip 18 projecting rearwardly from an outer periphery of the front portion. A rearwardly-facing rear edge 18 a of the rim 18 (see FIG. 10) is bonded by silver-nickel brazing 22 to a forwardly-facing seat 20 of the body 12. The seat 20 is bordered inwardly by a forwardly-projecting ridge 21 of the body which extends endlessly around the seat 20.

The shapes of the seat and the mating surface of the rim can vary. For example, the forwardly facing seat of the body could comprise a forwardly open recess 20′ disposed between two endless ridges 21′, 21″ of the body as shown in FIG. 3 a. The rear edge of the rim 18 would include a rearwardly projecting rib 22′ that fits into the recess 21′. As in the case of FIGS. 1-6, the rear edge of the rim would be bonded to the seat by silver-nickel brazing. Alternatively, the positions of the recess 21′ and the rib 22′ could be reversed, i.e., the recess could be disposed in the rim, and the rib on the body.

The body 12 is formed of stainless steel, most preferably 17-4 stainless steel, and the face member 14 is formed of a titanium alloy, most preferably 15-3-3-3 beta titanium, although other stainless steel materials and other titanium alloys could be used.

It will be appreciated that a cup-shaped face member provides a vertically longer “sweet” area of the front face as compared to a prior art TIG (tungsten inert gas) welded-on flat titanium faceplate 30 (FIG. 9). That is, in FIG. 8 it can be seen that the height H of the sweet area of the cup-shaped face member 14 extends virtually from the top edge 31 to the bottom edge 32 of the club's front face, whereas FIG. 9 shows that the height H′ of the sweet area of the prior art faceplate 30 terminates short of the top and bottom edges.

The front portion 16 of the face member 14 is preferably of variable thickness (see FIGS. 8 and 10) in that the center region 16 a thereof is thicker than the outer peripheral border portion 16 b thereof, whereby the face member performs a robust spring action upon impact, to maximize the ball's travel distance. For example, the center portion could be 2.6 mm thick, and the outer peripheral portion 1.6 mm thick. It will be appreciated that if a prior art variable-thickness faceplate 30 is attached by a TIG weld to a body, the weld will coincide with a thin outer portion of the faceplate, thereby stiffening that welded thin outer portion and reducing its flexibility. That will not occur in the present invention since the brazing 22 is spaced from the thin outer border region of the front portion 16 by the rim 18 of the faceplate. Accordingly, the spring action of the variable-thickness titanium face member 14 according to the present invention is not appreciably reduced by the weld could occur in the prior art.

Instead of becoming gradually thinner toward the outer periphery, as shown in FIGS. 8 and 10, the center region of the front portion 16 could be of a constant larger-thickness surrounded by a constant smaller-thickness border portion.

Furthermore, since the top, bottom, and sides of the club's front face are formed by the thin border portion of the face member 14, rather than by the thicker and heavier stainless material of the club body 12A (as in the prior art shown in FIG. 9), there will occur a reduction in weight of the club head. An additional weight reduction occurs as a result of the use of silver-nickel brazing to attach the face member 14, which brazing is lighter (e.g., on the order of about seven grams) as compared to the TIG weld used in the prior art.

The thus-achieved reduction in weight can serve to lower the center of gravity of the club head and thereby lengthen the length x of the effective hitting area of the front face, as shown in FIG. 7. Accordingly, the occurrence of backspin on a hit ball can be reduced.

Moreover, by reducing the weight at the front face of the club head (by replacing stainless steel with titanium and silver-nickel braze), the center of gravity becomes located deeper in the club (i.e., the distance GD in FIG. 7 is increased), thereby promoting greater elevation of a hit ball, and more forgiveness of off-center hits. The large, generally rectangular shape of the front face of the club (see FIG. 1) also provides greater forgiveness of off-center hits as compared to smaller-area trapezoidal-shaped front faces of prior art fairway clubs.

Alternatively, the above-described weight savings make it possible to add weights to the club head in order to achieve various additional advantages without making the club excessively heavy. For example, as shown in FIGS. 2 and 6, a pair of weights 40, 40 in the form of rods are attached at the toe and heel, respectively, of the body 12. Preferably, those rods are welded in respective holes formed in the toe side and heel side of the body, the axes of the holes extending in the fore-aft direction of the club head. Each rod 40 preferably comprises a tungsten nickel rod having a weight of about 4 grams, for example. The effect of those rods is to increase the weight of the toe and heel regions and thereby increase the inertia of those regions during a swing in order to better resist the tendency for the club head to twist in the event of an off-center hit.

A pair of weights 44 may be attached in the sole 46 of the body near the front face and on opposite sides of a front-to-rear centerline CL of the club head. Each weight 44 could preferably comprise a tungsten-nickel screw having a weight of 10 grams, for example, that is permanently bonded in the body 12. The effect of those weights 44 is to advantageously lower the center of gravity of the club head.

To further reduce the weight of the club head, especially at the top (and thus to lower the head's center of gravity), the hosel 50 comprises a stainless steel inner portion 52 (integral with the body 12) and a titanium alloy outer sleeve portion 54 welded to the inner portion. The outer sleeve portion 54 preferably comprises an alpha-beta titanium alloy such as 6-4 titanium, for example. This can reduce the weight of the top of the head by about 3 grams, thereby advantageously lowering the center of gravity.

FIG. 11 depicts schematically a fairway wood club head profile according to the invention wherein the portion 60 of the sole disposed in a region extending rearwardly from about a vertical center line L of the head to the back end 62 is inclined upwardly (cambered) as shown in FIG. 11, whereby the length of the horizontal flat ground-engaging portion 64 of the sole is minimized. This short flat horizontal portion 64 makes it easier for the head to rest on the ground. Also, it is easier to make the club head airborne at the start of the backswing since the ground-engaging area of the sole has been minimized in the rear half of the head.

In contrast, FIG. 12 depicts the sole 72 of a prior art head which exhibits a substantially longer ground flat horizontal engaging area and is more difficult to make airborne.

The club head 10 is preferably used with a conventional triple-action shaft (not shown) which includes a tip zone to which the club's hosel is attached, a butt zone which is gripped by a player, and a middle zone disposed between the tip zone and the butt zone. The tip zone is the most flexible; the butt zone is more rigid (less flexible) than the tip zone; and the middle zone is more rigid than the butt zone in order to: control the stability of the swing, improve the directional accuracy of a shot, and increase the head speed.

It will be appreciated that a fairway wood according to the above-described invention exhibits a unique combination of features, including:

-   -   a vertically longer “sweet” area on the front face     -   a highly springy front face for increased distance     -   lighter club head, and/or a club head having weight reductions         in certain areas and weight increases in other strategically         selected areas for better resisting twisting of the club head         during impact     -   a club head having a center of gravity which is situated         vertically lower and/or horizontally deeper, for reduced         backspin and increased elevation of a shot     -   a club head which more easily becomes airborne during a         backswing.

Although the present invention has been described in connection with a preferred embodiment thereof, it will be appreciated by those skilled in the art that additions, deletions, modifications, and substitutions not specifically described may be made without departing from the spirit and scope of the invention as defined in the appended claims. 

1. A fairway wood comprising a body and a face member attached to a front side of the body, the face member including a front portion and a rim projecting rearwardly from an outer periphery of the front portion, the front portion defining a front face of the wood, a rear portion of the rim being bonded to a seat of the body, wherein the body comprises stainless steel and the face member comprises a titanium alloy, wherein a rear end edge of the rim is bonded to the seat of the body by silver-nickel brazing.
 2. The fairway wood according to claim 1 wherein the face member comprises beta titanium.
 3. The fairway wood according to claim 2 wherein the beta titanium is a 15-3-3-3-beta titanium alloy.
 4. The fairway wood according to claim 1 wherein the front portion of the face member is thicker at a center region thereof than at an outer peripheral portion thereof.
 5. The fairway wood according to claim 4 wherein the thickness of the front portion gradually increases from the outer peripheral portion to the central portion.
 6. The fairway wood according to claim 1 wherein the seat is bordered inwardly by a forwardly projecting ridge of the body.
 7. The fairway wood according to claim 6 wherein the seat comprises a recess formed in one of the body and the rim, and a rib formed on the other of the body and the rim and received in the recess.
 8. The fairway wood according to claim 1 further comprising first and second weights mounted in a sole of the body on opposite sides of a horizontal front-to-rear centerline of the body.
 9. The fairway wood according to claim 8 further comprising third and fourth weights mounted in a toe portion and a heel portion, respectively, of the body.
 10. The fairway wood according to claim 1 wherein the body comprises stainless steel, and further including a hosel comprising a stainless steel cylindrical inner portion defined by part of the body, and a cylindrical outer sleeve portion telescoped onto and bonded to the inner portion, the outer portion formed of a titanium alloy.
 11. The fairway wood according to claim 1 wherein the body includes a sole, a front portion of the sole being flat and horizontal; a rear portion of the sole being inclined upwardly and rearwardly from a location substantially midway between front and rear ends of the body.
 12. A fairway wood comprising a body, a face member attached to a front side thereof, and four weights mounted in the body; first and second ones of the weights being mounted in a sole of the body on opposite sides of a horizontal front-to-rear centerline of the body; third and fourth ones of the weights being mounted in toe and heel portions, respectively, of the body.
 13. The fairway wood according to claim 12 wherein the body comprises stainless steel, the face member comprises a titanium alloy, and the four weights comprise a titanium alloy.
 14. A fairway wood comprising a body and a face member attached to a front side thereof, the body including a sole, a front portion of the sole being flat and horizontal; a rear portion of the sole being inclined upwardly and rearwardly from a location substantially midway between front and rear ends of the body.
 15. A fairway wood comprising a body, a face member attached to a front side thereof, wherein the body comprises stainless steel, and further including a hosel comprising a stainless steel cylindrical inner portion defined by part of the body, and cylindrical outer portion telescoped onto and bonded to the inner portion, the outer portion formed of a titanium alloy.
 16. A fairway wood comprising a stainless steel body and a titanium alloy face member attached to a front side of the body, the face member including a front portion and a rim projecting rearwardly from an outer periphery of the front portion, the front portion defining a front face of the wood, a rear portion of the rim being bonded to a seat of the body by silver-nickel brazing, wherein the front portion of the face member is thicker at a center region thereof than an outer peripheral region thereof, first and second weights mounted in a sole of the body on opposite sides of a horizontal front-to-rear centerline of the body, and third and fourth weights mounted in toe and heel portions, respectively, of the body.
 17. The fairway wood according to claim 16 wherein the body comprises stainless steel, and further including a hosel comprising a stainless steel cylindrical inner portion defined by part of the body, and a cylindrical outer portion telescoped onto and bonded to the inner portion, the outer sleeve portion formed of a titanium alloy.
 18. The fairway wood according to claim 16 wherein the body includes a sole, a front portion of the sole being flat and horizontal; a rear portion of the sole being inclined upwardly and rearwardly from a location substantially midway between front and rear ends of the body. 